Internal-combustion engine



I s. B. ARNOLD,- INTERNAL COMBUSTION ENGINE.

APPLICATION FILED MAR. 28. 191B.

Patented June 3, 19l9.

S. B. ARNOLD. INTERNAL COMBUSTiON ENGINE.

APPLICATION FILED MAR. 28 191B.

' Patnfed June 3, 1919'.

5 SHEETSSHEET 2.

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S. B. ARNOLD. INTERNAL COMBUSTION/ENGINE. APPLICATION FILED MAR. 28. 1-918.

5 SHEETS-SHEET 3.

Patented June 3, 1919.

S. B. ARNOLD. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED MAR. 28. I9III. I

Patented J 11116 3, I919. 1

5 SHEETS-SHEET 4 fweizzbf- M g r 2 ma 5 i is non-rotatable and UNITED STATES PATENT OFFICE.

STANLEY .B. ARNOLD, OI CHICAGO, ILLINOIS.

m'rnmmL-comius'rron ENGINE.

To all whom it may concern: I

Be it known that I, STANLEY B. ARNOLD, citizen of the United States, residing at Chi cago, in the county of Cook and State of Illinois, have invented a certain new and useful Improvement in Internal- Combustion Engines, of which the following is a full, clear, concise, and exact description.

My invention relates to internal combustion engines employing cylinders distributed around the crank shaft, the cylinders as a unit and the shaft being relatively rotatable. As I have embodied my invention the shaft the cylinders rotate bodily around the shaft, thoughI do not wish to be limited to these characteristics. I employ two relatively offset cranks and arrange the cylinders in two sets with the pistons of one set in operative connection with one crank and the pistons of the other set in operative connection with the other crank, the pumping chambers of each cylinder of each set being in communication with the explosion chamber in a cylinder in the other set that operatively succeeds the first cylin der.

In the preferred embodiment of the invention thecylinders of each set alternate with cylinders of the other set to form a composite series of cylinders.

I will explain my invention more fully by reference to the accompanying drawings showing the preferred embodiment thereof and in which Figure 1 is a view taken on a plane that includes the axes of the cylinders of one set, it being preferred to arrange the two sets of cylinders in different planes; Fig. 2 is a view on line 2-2 of Fig. 1; Fig. 3 is a developed view looking down upon the engine, some of the structure being shown in section; Figs. 4, 5 and 6 are views illustrative of puppet exhaust valve actuating mechanism; Fig. 7 is a timing diagram; and Fig. 8 is a view somewhatsimilar to Fig. 1 except that this figure is morediagrammatic and also the cylinders of both sets are illustrated in this figure as being in the same plane with the corresponding modifications.

Like parts are indicated by similar characters of reference throughout the different figures. Y

The engine is built up around a crank shaft provided with angularly related cranks preferably spaced apart 180, if there are but two cranks. crank shaft is stationaryand the crank case,

therein. The pistons of bodies that respectively As illustrated, the

Specification of Letters Patent. I Patented June 3, 1919, Application filed March 28, 1918. Serial No. 225,229.

The engine" illustrated has twelve cylinders A, B, C, D, E, F, G, H, I, J, K, and L which are mounted in a crankcase M, the inner ends of the cylinders opening into the crank case. These cylinders two sets, the cylinders A, C, E, G, I and K being 1n one-set and the remaining cylinders being in the other set. In, order that the diameter of the engine, as a whole, may be reduced as much as possible while accommodating all of the cylinders of the engine and in order that there may bea most desirable construction and arrangement of the crank shaft, the cranks pertaining to the two sets. ofcylinders, and a most desirable construc tion in general, the. two sets of cylinders are arranged in different planes, the cylinders of one set being in staggered relation to the cylinders of the other set. I do not wish to be limited, however, to this arrangement. Each cylinder has a piston 1 reciprocating cylinders G and J are connected by p-itme-n 2 and 3 respectively with the crank pins l and-5 which are at the inner ends of said pitmen. These crank pins are angularly displaced, the axis of the crank shaft 6 lying between said crank pins which are desirably separated 180. The inner ends of these pitmen are desirably enlarged to form circular mounting plates or support what may be termed wrist pins. that. pertain to the pitman 2- and the to the pitman 3. The pistons of the cylinders remaining in the set A, C, E, G, I and K are connected by the pitmen 9 with the wrist pins 7 that are carried by the pitman 2. The pistons of the cylinders remaining in the set B, D, F, H, J and L are connected by the pitmen 10 with the wrist pins 8 that are carried by the pitman 2.

The pistons are of the differential type and the cylinders are made so that their inside diameters of their inner parts are considerably greater than the diameters of the outer parts of said cylinders to accommodate" the corresponding parts of the pistons that are of different diameters to make them differential. There are in each cylinder two chambers 11 and 12, the chamber wrist pins 8 that pertain are arranged in ing the explosion chamber.

11 at the inner end being a pumping chamber and the chamber 12 art the outer end he- Each cylinder has also an annular receiving chamber 13 at its Inidportionwhich communicates with the explosion chamber through charging ports 14 arranged around the cylinder so that the piston uncovers them when itreaches the inner limit of its stroke. There are also intake ports 15 arranged around the cylinder where it projects into the crank case M so that the lower partof the piston uncovers them when the piston has reached the inner limit of its stroke in the cylinder. The pumping chamber 11 of each cylinder of one set is connected with the annular' receiving chamber 13 of the next cylinder of the other set by a tubular connector 16 preferably in the direction in which the crank case and cylinders are revolving. One section of the crank shaft 6 is hollow and is held from rotation by a crank shaft support 17. Cam disks 18, one pertaining to each set of cylinders, are carried by the sections of the crank shaft. Cam rods 19 reciprocate through the guides 20 carried by the crank case M and carry rollers 21 upon their inner ends, these rollers being pressed by springs 22 against the peripheries of said cam disks. These cam rods operate links 23 Whose outer ends are connected with tappets 24 that control the puppet exhaust valves 25 in the outer ends of the cylinders. The'se valves are closed by the springs 26 and are opened by the tappets operating against said springs.

A carbureter 27 is connected with the hollow section of the crank shaft 6 that is mounted in the support17. This carbureter has a throttle 28 and an extra air valve 29. Thereis a lubricating oil tube 30 entering into the side of the hollow end of the crank shaft close to the carburetor and extending into the hollow crank shaft section and enteringthe web of one of the cranks. The webs of the cranks and the crank pins contain small oil passages 31. The crank caseis supported by ball bearings 32 in its end walls. There is a large gear wheel 33 attached to the end wall of the crank case that is .adjacent the support 17 for driving a magneto and the fuel and oil pumps, etc. This gear carries a distributer 34 for high tension current to ignite the charges of compressed fuel and air mixture in the cylinders. The insulated pins 35 forming contact with the metal segments in this distributer, are shown fixed in the supporting structure 17.

Where the crank shaft is stationary the load is attached to the crank case, Fig. 2 illustrating the termination of the crank shaft at the left side of the crank case, the side farthest removed from thesupportln'g member 17.

. The crank case formsan inclosed chamber, the entrance of air except through the hollow crank shaft being prevented at one end by a ring piece 36 which screws up against the ball bearing and has close contact with the outside of the crank shaft and at the other end by the short shaft piece 37 that is bolted to the end of the crank case for carrying the propeller and for forming a surface for the supporting bearing 38. Spark plugs 39 are employed for igniting the charges of fuel and air mixture in the cylinders.

Figs. 4, 5 and 6 show the operation of camdisks 18 upon the cam rollers 21 and while I prefer the illustrated construction, of operating mechanism and exhaust means, I do not wish to be limited thereto. Fig. 4 illustrates the cam that is at the end of the crank shaft next to the supporting structure 17 in its position as it is on the crank shaft in Fig. 2, and Fig. 5 shows the cam that is at the other end of the crank shaft. Fig. 6 shows the relative positions of the two cams and the two cranks.

In order to show each cylinder clearly I have relatively increased the diameter of the crank case in Fig. 8. The twelve cylinders are shown placed around the circular crank case with six of the cylinders acting upon one crank pin, the other six cylinders acting on the other crank pin, as is understood.

The piston in cylinder A is shown at the outer limit of its stroke. The piston of cylinder B has at this time started upon its out stroke and is just about to close the charging ports 14 through which the annular receiving chamber 13 of cylinder B communicates with the explosion chamber 12 of this cylinder. Therefore, when the crank case and cylinders revolve in the direction shown by the arrow, the piston-of cylinder A of one set of cylinders moves inwardly and the piston of cylinder B of the other set of cylinders moves outwardly. The result is that the piston of cylinder A creates a partial vacuum in the pumping chamber 11 of the cylinder and in the tubular connector 16 between the pumping chamber 11 of this cylinder and the annular receiving chamber 13 of cylinder B and in the annular receivlng chamber of this latter cylinder. The piston of cylinder C is shown after starting on its in stroke, and the piston of cylinder E is farther inward. The piston of cylinder G is shown at the inner limit of its stroke. As it approached the inner limit of its stroke, the piston of cylinder-G began to uncover the intake ports 15 arranged around the cyl- The crank case and cylinders continue revolving and the piston in cylinder G now starts on its out stroke. At the same instant,

the piston of cylinder A, which reached the outer limit of its stroke at the same instant that the piston of cylinder G reached the inner limit. of its stroke, starts on its in stroke. The piston of cylinder G, in moving. out wardly, closes ports 15 and compresses the fuel and air mixture contained the pumping chamber of this cylinder and in the tubular connector 16 between the pumping chamber of this cylinder and the annular receiving chamber of cylinder H and in the annular receiving chamber of this cylinder.

The pistons of cylinders I and K are shown L are shown on their inward or explosion strokes. As each piston on its in stroke nears a position to uncover the charging ports 14 of its cylinder, the puppet valve 25 pertaining to such cylinder is opened. Most of the spent gas is exhausted through the puppet exhaust valve opening before the charging ports are opened with the result that the pressure of the portion of the spent gas remaining in the explosion chamber is substantially atmospheric and therefore materially less than the pressure of the mixture in the annular receiving chamber 13 of the cylinder. When the piston uncovers the charging ports 14 through which the annular receivlng chamber 13 and the explosionv chamber 12 communicate, the fuel and air mixture that has been compressed in .the

pumping chamber 11 of the following cyl-- inder (which is in the other circular set) passes into the explosion chamber by way of the tubular connector 16 between the-Y;v

pumping chamber of said following cylinder and the receiving chamber whose charging ports are opened. The puppet valve of the chamber remains open for about 130 of a revolution, the puppet valve not closinguntil a fresh charge'has.

been fully admitted and which fresh charge expels practically all of the spent gas admitted.

It is evident that the amount of fuel and air mixture that goes into the explosion chamber of the cylinder depends upon the volume of the pumping chamber of the ad- 'acent cylinder that charges the explosion chamber of the cylinder ahead of it.

Cylinder G of the other set is shown with its piston at the inner limit of its stroke after completely uncovering the charging ports through which the annular receiving chamber communicates with the explosion chamber of the cylinder. The puppet'exhaust valve is shown wide open.

Cylinder Brisshown with its piston after it has started on its outward stroke and as it is in the act of closing the charging ports 14 through which the annular receiving chamber 13 of the cylinder communicates with the explosion chamber 12. The puppet exhaust valve in cylinder B has started to close but is still about half open. It closes when the crank case andcylinders revolve a few degrees farther to inclose the charge of fresh fuel mixture in the explosion chamber of the cylinder. After the exhaust valve has closed the piston in its out stroke compresses the charge'of fuel mixture in the explosion chamber of the cylinder. The pistons of cylinders D and F are shown moving outwardly in compressing the mixture. When the piston in each cylinder aproaches or reaches the outerlimit of its stroke, as shown in cylinder A, the com pressed charge of mixture is ignited by the spark plug 39 or some other suitable means, and the charge explodes and the piston starts moving inwardly on its explosion stroke. The pistons in cylinders H, J- and L are shown as moving inwardly on their explosion strokes, the exhaust valve in cylinder Lhaving started to open, as described before.

While I have herein shown and particularly described the preferred embodiment of my invention I do not wish to be limited to the precise details of construction shown as changes may readily be made without departing from the spirit of my invention, but having thus described my invention I claim as new and desire to secure by Letters Patent the following Y 1. An internal combustion engine includ" ing a shaft having two relatively offset cranks; two sets of cylinders with their pis- .tons which are'distributed around the crank shaft, the pistons of'one set being in operative connection with one crank and the pistons of the other set being in operative connection with the other crank, the cylinders ing chamber and an explosion chamber, the

pumping chamber of each cylinder of each i set being in communication with the explosion chamber in a succeeding cylinder in the other -set';' and means for establishing and breaking such communication.

2. An internal combustion engine including a shaft having two relatively offset cranks; two sets of cylinders with their pistons which are distributed around the crank shaft, the pistons of one set being 1n operative connection with one crank and the pistons of the other set being in operative connection with the other crank, each cylinder having a pumping chamber and an explosion chamber, the pumping chamber of each cylinder of each set being in communication with the explosion chamber in a succeeding cylinder in the other set, each pumping chamber and explosion chamber with which it is in connection being each individual to the other to the exclusion of other such chambers; and means for establishing and breaking such communication.

3. An internal combustion engine including a shaft having two relatively offset cranks; two sets of cylinders with their pistons which are distributed around the crankshaft, the pistons of one set being in operative connection with one crank and the pistons of the other set being in operative connection with the other crank, the cylinders of one set alternating with the cylinders of the other set to form a composite series of cylinders around the crankshaft, each cylinder having a pumping chamber and an explosion chamber, the

pumping chamber of each cylinder of each set being in communication with the explosion chamber in a succeeding cylinder of the other set; and means for establishing and breaking such communication, the connecting passages between the pumping chambers of the cylinders of one set and the explosion chambers of the cylinders of the other set being so arranged that the component of the flow through these passages when the pumping chambers of the cylinders of one set are charging the explosion chambers of the cylinders of the other set which component is in a direction tangential to the crankshaft is always substantially in the same direction tangentially to the crankshaft in all these passages, relatively to these passages, irrespectively-0f the direction of rotation of the rotating element of the engine.

4. An internal combustion engine including a shaft having two relatively oflset cranks; two sets of cylinders with their pistons which are distributed around the crankshaft, the pistons of one set being in operative connection with one crank and the pistons of the other set being in operative con nection with the other crank, the cylinders of one set alternating with the cylinders of the other set to form a composite series of cylinders around the crankshaft, each cylinder having a pumping chamber and an explosion chamber, the pumping chamber of each cylinder of each set being in communication with the explosion chamber in anadjacent cylinder of the other set, and means for establishing and breaking such communication, the connecting passages between the pumping chambers of the cylinders of one set and the explosion chambers of the cylinders of the other set being so arranged that the component of the flow through these passages when the pumping chambers of" the cylinders of one set are charging the explosion chambers of the cylinders of the other set which component is in a direction tangential to the crankshaft is always substantially in the same directiontangentially to the crankshaft in all these passages, relatively to these passages, irrespectively of the direction of rotation of the rotating element of the engine.

5. An internal combustion engine including a shaft having two relatively offset cranks; two sets of cylinders with their pistons which are distributed around the crank shaft, the pistons of one set being in operative connection with one crank andthe pise tons of the other set being in operative connection with the other crank, the cylinders of one set alternating with the cylinders of the other set toform a composite series of cylinders around the crankshaft, each cylinder having a pumping chamber and an explosion chamber, the pumping chamber of each cylinder of each set being in communication with the explosion chamber in an adjacent cylinder of the other set; and means for establishing and breaking-,such communication.

In witness whereof, I hereunto subscribe my name this 25th day of March, A. D. 1918.

STANLEY B. ARNOLD. 

